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    <title>Document</title>
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<script>
      function gcd(x,y){
        if(y>x){ 
            var temp = x;
            x = y;
            y = temp;   
        }
        var mod = x % y; 
        if(mod == 0){ 
            return y;
        }
        return gcd(y,mod);
    }
    function lcm(x,y){
        return (x * y) / gcd(x, y);
    }
    console.log(gcd(4,12));
    console.log(lcm(4,12));
</script>

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